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3

The exact composition of iridium nitrite hasn't been determined because the compound has been poorly studied, although it is predicted to be $\ce{Ir(NO2)3}$ or $\ce{Ir(NO2)4}$ as +3 and +4 are the most common oxidation state. It is prepared by reacting iridium oxide with sodium nitrite at 333 K(1) or digesting "chloro compound of iridium" with hot ...


3

When two isolated atoms collide the total energy and momentum must remain with the two atoms so both are conserved overall. In fact in a reaction such as $\ce{H\cdot + H\cdot <=> H2}$ the hydrogen molecule only lasts for a few femtoseconds. This is because even though the bond is formed the atoms will still approach one another (total energy being ...


23

$\ce{C + O2}$ is awfully complicated, so let's just pretend you've asked this: In a single act of the reaction $\ce{H. + H .-> H2}$, how is momentum conserved? That's a legitimate concern all right. After all, we are taught that this reaction does happen instantly, once given a chance, and that's in fact true. Also, we know that it releases a lot of heat. ...


3

First, remember that the + and - on the lobes of an electronic wavefunction do not ever represent or suggest electronic charge. An electron is always negative; a proton (or nucleus) is always positive. In order to imbed this firmly in your mind without + or - signs, imagine one lobe of a p-orbital flashing red while the other flashes blue. In this picture, ...


0

The phosphate ion is of vital importance in biological systems. Its molecular geometry is tetrahedral. Thus, based on the $\mathrm{pH}$ of the system, hydroxy groups are inter-changeable with $\ce{P=O}$ form and hence all three remaining $\ce{O}$s are equivalent (see Waylander's comment). Therefore no impact on the dehydration. However, the stereochemistry ...


1

$\ce{HCN}$ and $\ce{HC#CH}$ are linear, triple bonded, with a $π$ system consisting of two perpendicular $π$ bonds. They would be symmetrical in $\ce{HC#CH}$, and slightly distorted in $\ce{HCN}$, and they leave two orbitals for the sigma system. In $\ce{HCN}$, we hybridize/combine the two remaining orbitals on the carbon atom to form two bonding orbitals, ...


1

Hypervalency is real, yes. Hypervalency is the ability of an atom in a molecule to expand its valence shell beyond the limits of the Lewis octet rule. Hypervalent compounds are common for the second and subsequent row elements in groups 14–18 of the periodic table. Half bonds don't exist. The closest thing to a half bond is e.g Li2+, H2+. Its a one-electron ...


0

Although for a halide we can easily recognise that the natural tendency is to exist with that extra electron, for a lot of elements the case is not so straightforward. For example, most transition elements can exist in multiple ionic states, and for elements like carbon, mostly covalent bonds are formed. The ground state configurations are not by any means a ...


-5

Some search on bond angle data for NCl3 and NH3. Many places, it is mentioned that bond angle of NCl3 > NH3 but no references are given. I looked around to find some experimental data on this. To my search bond angle in NCl3 (107) < NH3 (107.8). Here are the references for my analysis. In case of NCl3: (1) http://www.chm.bris.ac.uk/motm/ncl3/ncl3js....


2

We may not produce nails from our bodies, but certain enzymes and proteins do involve metal clusters, especially clusters involving iron [1]. In the natural biomolecules iron-iron and iron-nickel compounds serve as functional groups for electron transfer. Also discussed are iron-sulfur clusters, which have characteristics similar to all-metal clusters ...


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